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Highly conductive, thermally insulating, and three-dimensional (3D) macromolecular network-structured nanocomposite biofoams with very low density were designed from soy oil-based polyurethane (PU) and hydroxyl-functionalized multiwalled carbon nanotubes (MWCNT-OH) using a facile one-pot process with water as the sole blowing agent. Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and Fourier Transform Infrared spectroscopy (FTIR) analyses revealed homogeneous dispersion as well as interaction or reaction of MWCNT-OH with the PU biofoam matrix or a polymeric methylene diphenyl diisocyanate (MDI) to form a 3D macromolecular network structure. Mechanical properties and electrical conductivity were remarkably enhanced with the increase of MWCNT-OH. Dynamic mechanical analysis and thermogravimetric analysis results showed that all the nanocomposite PU biofoam products had good thermal stability properties. Hence, the prepared nanocomposites hold promise as rigid biopolyurethane (BioPU) foams, serving the needs of the conductive composite material fields.Keywords Biofoam Á MWCNT-OH Á Soy-based polyol Á One-pot method J Am Oil Chem Soc (2019) 96: 319-328.

Adsorption and desorption behaviors of tetracycline hydrochloride by activated carbon-based adsorbents derived from sugar cane bagasse modified with ZnCl 2 were investigated. The activated carbon was tested by SEM, EDX, BET, XRD, FTIR, and XPS. This activated carbon exhibited a high BET surface area of 831 m 2 g −1 with the average pore diameter and pore volume reaching 2.52 nm and 0.45 m 3 g −1 , respectively. The batch experimental results can be described by Freundlich equation, pseudo-second-order kinetics, and the intraparticle diffusion model, while the maximum adsorption capacity reached 239.6 mg g −1 under 318 K. The effects of flow rate, bed height, initial concentration, and temperature were studied in fixed bed adsorption experiments, and adsorption data were fitted with six dynamic adsorption models. The results of characterizations and the batch experiments were analyzed to study the adsorption and desorption mechanisms. Tetracycline hydrochloride and activated carbon were bonded together by π-π interactions and cation-π bonds. Ethanol was used as an eluent which bonded with 10 hydrogen bond acceptors on tetracycline hydrochloride to form a complex by hydrogen bonding to achieve recycling.Molecules 2019, 24, 4534 2 of 17 has numerous -OH groups, some of which remain in the pyrolysis, while other parts forms new chemically-reactive oxygen functional groups [6]. AC contains not only a benzene ring but also many chemically reactive oxygen functional groups (-OH, -COOH, etc.), which can be used for chemical modification [7]. The -NH 2 group in the TCH can form a π-π interaction and a cation-π bond with the benzene ring on the ZnCl 2 activated bagasse-based activated carbon (ZBAC). During the pyrolysis process, cellulose and hemicellulose in bagasse (about 50 wt% cellulose and 25 wt% hemicellulose) are decomposed at 202 • C to produce levoglucosan (LGA) and anhydrosugar polymers. The isomerization reaction occurs after LGA dehydration which forms other anhydrosugars and furans [8]. The pyrolysis product is polymerized to form activated carbon at 600 • C. The activated carbon produced by direct the pyrolysis of bagasse has a small specific surface area (S BET was about 376.08 m 2 g −1 ), and ZnCl 2 helps to form more porous structures during pyrolysis (S BET was about 831.23 m 2 g −1 ) because ZnCl 2 catalyzes the Scholl condensation reaction during pyrolysis. The above-mentioned macromolecular polycyclic compounds in bagasse form porous structures during pyrolysis at high temperatures [9].However, how activated carbon's effect on the fate of tetracycline hydrochloride (TCH) in water has become a question demanding a quick solution, and few reports have paid attention to the adsorption and desorption behavior and mechanism. Desorption behavior influences not only the fate of TCH in the environment, which is still a primary concern, but also the efficient recycling of the adsorbent [10]. The structure-activity relationship of adsorbents plays a significant component in the adsorption and desorption process....

It is challenging to prepare polyurethane bioplastics from renewable resources in a sustainable world. In this work, polyurethane nanocomposite bioplastics are fabricated by blending up to 80 wt % of soy-based polyol and petrochemical polyol with hydroxyl-functionalized multiwalled carbon nanotubes (MWCNTs-OH). The scanning electron microscope (SEM), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FTIR) analyses reveal homogeneous dispersion of the MWCNTs-OH in the matrix, as well as interaction or reaction of MWCNTs-OH with the matrix or polymeric methylene diphenyl diisocyanate (pMDI) in forming the organic–inorganic hybrid bioplastic with a three-dimensional (3D) macromolecule network structure. Mechanical properties and electrical conductivity are remarkably enhanced with the increase of the multiwalled carbon nanotube (MWCNTs) loading. Dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) results show that the bioplastics with MWCNTs-OH have a better thermal stability compared with the bioplastics without MWCNTs-OH. The composition of the nanocomposites, which defines the characteristics of the material and its thermal and electrical conductivity properties, can be precisely controlled by simply varying the concentration of MWCNTs-OH in the polyol mixture solution.